Health care workforce shortages in primary care and underserved areas severely limit health care access to rural and lower socioeconomic communities, significantly contributing to the health care disparities faced by these communities. Physicians are one important component of the health care workforce and graduate medical education (GME) is a critical step in the production of the U.S. physician workforce. GME program factors, such as location, curriculum and mission affect graduate career choices. GME also represents the greatest federal investment in medical education, with teaching hospitals receiving over $9 billion annually in Medicare support for GME activities. However, comprehensive research examining the output of the GME system as a whole, including contributions of programs and the overarching characteristics of high primary care and underserved practice producers, is limited. Insufficient research limits the ability to produce effective evidence based policies around GME. The goal of the proposed research is to examine the output of U.S. GME sponsoring institutions and identify the characteristics of successful primary care and underserved practice producing institutions. This study will use existing datasets (the American Medical Association Physician Masterfile, National Provider Identification database, and Medicare claims data) to identify physicians' graduate medical education training institutions and examine the relationship between training institution characteristics and eventual practice in primary care and underserved areas. We will also examine the relationship between physician Medicare spending practice patterns and the spending patterns of their training institutions. Cost effective practice will be critical to maintaining a high functioning, accessible health care system in the future and a better understanding of the factors influencing physician spending practice patterns will help to establish such a cost effective system. Finally, we will examine the Teaching Health Centers model, identifying health centers that are currently training physicians and determining the eventual practice location of these physicians. Teaching Health Centers legislation was passed in the Patient Protection and Affordable Care Act of 2010 and represents a new model of federal support for GME programs. Understanding current training and the outcomes of this model is relevant to current and future policy. In all cases, increasing the level of understanding of graduate medical education will lead to evidence based policies to address health care access and disparities issues.